/**
 * User:langchen
 * Date:2022-07-27
 * Time:14:59
 */
public class count9 {
    public static void main(String[] args) {
        int sum =0;
        int i =0;
        for(i=1;i<=100;i++){
            if(i%9==0){
                sum++;
            }
            else if(i/9==0){
                sum++;
            }
        }
        System.out.println(sum);
    }
}
